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Unread 18-03-2012, 19:49
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Re: PID control: need D values > 10000??

Quote:
Originally Posted by dtgriscom View Post
Why does this require such enormous values of D?
According to this post, D is multiplied by the difference in error, not by the (difference in error)/(sample time). Since the PID in the Jag runs at 1000Hz, that factor of 1000 needs to be in your D gain. That's my guess.

What's the resolution (counts per degree) of your encoder, and how fast are you moving the arm (degrees per millisecond) when you're looking for a voltage?


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